Shutter for projecting apparatus.



UNITED STATES PATENT orr on.

ALmNDER G. DONNELLY, OF NEW YORK, N. Y., ASSIGNOR TO QUASAPIC COMFANY, INC., OF NEW YORK, N. Y., A CORPORATION OF NEW YORK. Y

SHUTTER FDR PROJECTING 'APPARATUS.

Specification of Letters Patent.

PatentedJune 2, 1914.

Original application filed May 15, 1912, Serial No. 697,383. Divided and this application filed December 2, 1912. Serial No. 734,479.

To all whom it may concern Be it known that I, ALEXANDER G. DON- NELLY, a citizen of the United States, residing in New York city, in the county of New York and State of New York, have invented certain new and useful Improvements in Shutters for Projecting Apparatus, of which the following isa specification.

My present invention constitutes an improved exposure shutter adapted to cause exposures initiated on and substantially radially dilated from the focal axis, and closures marginally initiated substantially radiallycontracted and completed on the axis; said shutter, while of general adaptation, being especially adapted for use in kinematic color apparatus such as disclosed in my copending application, Serial .No. 697 ,383, filed May 15, 1912, of which this application is a division.

In the accompanying drawings, showing one embodiment of my invention, Figure 1 is an axial sectional elevation showing a portion of a projecting apparatus with the shutter. Fig. 2 is a corresponding transverse view. Fig. 3 is an elevation of the shutters. Fig. 4 is an axial elevation of the central plug. Fig. 5 is a cross section on the line 5-5 of Fig. 1. Fig. 6 is a plan. of

the intermediate pinions of the shutter-gear train.

In the present embodiment the invention is applied to a projecting apparatus, especially adapted for motion picture machines.

A frame 1 is shown having a lens tube 2 secured in an opening by means of a nozzle 3, which extends said, tube into close proximity to and whose inner end is scribed to 'make a light-proof joint with the tubular shutter 93, and, adjustably mounted on the axes of the machine, by means of adjustment mechanisms 64 and 66, a vertical cylindrical plug 95 having lower and upper stems 96 and 65 which respectively engage said adjustment mechanisms, and containing an exposure slot 67 co-axial with the lens tube 2 and, transverse thereto, vertical through-slots 68 for color plates or screens, such as are used in kinemati-color machines.

The plug 95 is enveloped by a pair of revoluble tubular shutters 93 and 94, each having a pair of like, opposite, oblong, round-ended exposure slots respectively 79 and 80, and 73 and 74, separated by walls slightly wider than and adapted to cover the plug-slot 67, and which, during the operation otthe machine, alternate with said shutter slots in registering with the exposure slot 67 to cause closures and exposures and intermedlately to such registering, register withand cover and uncover the color-plate slots 68.

The shutters 93, 94, are revolved continubecomes complete when the intradoses of adjacent shutter-slot ends are tangent to one another; and complete exposure endures through an angular motion of the shutter equal to the angular length of the parallel sides of their slots, or while said slot-sides are passing one another. In other words, the shutters being revolved synchronously oppositely and their slots being circumferentially oblong with rounded ends, and angularly much Wider than the turret-slot 67 (which is illustrated in Fig. 2 as narrower than its height, which equals the diameter of the circles momentarily formed by the rounded ends of the shutter slots about at the beginning and end of full exposure), it is obvious that each full exposure lasts nearly as long as the margins of the turret slot is visible, at first between the reading, uncovering, and subsequently between the opposite approaching closing margins of the shutter slots. It will be seen that the action of these shutters in causing closures and exposures is as nearly like that of the iris of the human eye as it is possible to obtain with a simple mechanism, capable of high speed; that the graduated contraction and dilation of the exposure orifice prevents the objectionable flicker which is a common incident of moving pictures; and that when the exposure slot 67 is open the color plate slots '68 are covered, which prevents the intrusion photographing; and that no stray light can enter between the shutter and the tube nozzle 3.

- The shutters 93 and 94: may be revolved in any convenient manner. That illustrated is adapted to be driven from the transmission of a machine such as disclosed in my aforesaid application. The inner shutter 94 is fast to the head 72 of a sleeve 69 and thereby mounted on the lower stem 96 of the plug 95 and on balls 71, and is driven from said transmission by means of a'gear wheel 70 fast on said sleeve. The outer shutter 93, is fast to a perforated disk 81 mounted thereby and by balls 82, on the upper face of said plug, centered on its upper stem 65, and is driven oppositely to and angular speed, said slots adapted to initiate closure marginally, contract the opening substantially radially and complete closure on the focal axis and to initiate exposure on the axis and dilate the opening substantially radially.

2. A shutter for kinemati-color apparatus, comprising a fixed cylinder whose axis is perpendicular to a focal axis and containing an exposure opening coaxial there with and color-screen slots perpendicular thereto, a pair of-revoluble tubular shutters enveloping said cylinder and containing like exposure slots and means to revolve said shutters at equal angular speeds and in 0pposite directions.

3. A shutter for kinemati-color apparatus, comprising a fixed cylinder whose axis isperpendicular to a focal axis and containing an exposure opening co-axial therewith and color-screen slots perpendicular thereto, a pair of revoluble tubular shutters enveloping said cylinder and containing likeround-ended exposure slots and means to revolve said shutters at equal angular speeds and in opposite directions.

ALEXANDER G. DONNELLY.

Witnesses: I

FRED. J. DOLE, WM. H. Ben). 

